Microwave torrefaction of sawdust as biomass energy source
DOI:
https://doi.org/10.15282/jceib.v12i1.10900Keywords:
biomass, microwave, torrefaction, sawdust, energy sourceAbstract
Sawdust is a lignocellulosic waste generated from timber-processing activities and has potential as a renewable solid fuel. However, its direct use is limited by high moisture content and volatile matter, which reduce its fuel quality. This study aimed to enhance the chemical characteristics and fuel properties of sawdust through microwave-assisted torrefaction. Torrefaction was carried out under an oxygen-free nitrogen atmosphere at a microwave power of 1000 W. The effects of residence time, varied at 5, 10, 20, and 30 min, and nitrogen flow rate, varied at 30, 60, and 90 mL/min, were investigated. The torrefied sawdust was evaluated based on physical appearance, proximate properties, carbon content, and higher heating value (HHV), which refers to the total heat released during complete combustion of a fuel, including the latent heat recovered from water vapour condensation. The results showed that microwave torrefaction changed the colour of sawdust from light brown to nearly black, indicating carbon enrichment and volatile matter removal. The process reduced moisture content by 28%, increased HHV by 50%, and enhanced carbon content by 60%. These improvements were attributed to the thermal decomposition of biomass constituents and the release of volatile compounds during torrefaction. In conclusion, microwave-assisted torrefaction effectively improved the fuel quality of sawdust, suggesting that torrefied sawdust has strong potential as a renewable solid fuel for energy applications.
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